
Aulonocara sp. 'Firefish' - Tropical Fish for Sale UK
24–28°C · pH 7.5–8.5 · 200L

Baryancistrus sp.
A striking, high-contrast pleco from fast-flowing Amazonian waters that rewards experienced keepers with bold patterning and active grazing behavior. Difficult care, peaceful. 24-30C, pH 6.0-7.5.
Maintain these water conditions for optimal health and vibrant colors
The L177 Gold Nugget Pleco (Baryancistrus sp.) is a highly prized, strikingly beautiful freshwater aquarium fish renowned for its bold black body adorned with vivid golden-yellow spots and fin margins. Originating from the fast-flowing clearwater rivers of northern Brazil—likely the Xingu or Tapajós basins—this rare L-number pleco demands expert-level care, pristine water quality, and a spacious, high-flow aquarium setup. Available for sale UK from Tropical Fish Co, L177 specimens are carefully sourced and ideal for dedicated aquarists seeking a spectacular centerpiece catfish. This is not a beginner species, but for those prepared to meet its needs, the L177 offers unmatched visual impact and rewarding long-term keeping.
The L177 Gold Nugget Pleco displays a jet-black base coloration covered in bright golden-yellow spots that extend across the body, head, and dorsal fin. Fin margins are highlighted with vivid gold edging, creating a stunning contrast. Juveniles exhibit more uniform spotting, while adults may develop larger, more irregular markings. The body is robust and laterally compressed, with a broad, armored head and powerful pectoral fins. Adult males often develop odontodes (bristle-like growths) on the pectoral fin spines and cheeks. At maturity, this species can reach up to 28 cm, requiring substantial tank space and appropriate tankmates.
Baryancistrus sp. L177 inhabits clearwater river systems in northern South America, particularly the Xingu and Tapajós regions of Brazil. These environments are characterized by fast-flowing, highly oxygenated water, rocky substrates, submerged boulders, and abundant driftwood. Water chemistry is typically soft to moderately hard with neutral to slightly acidic pH. The rivers experience seasonal fluctuations in flow and temperature, but water quality remains exceptionally high. L177 plecos graze on biofilm, aufwuchs (algae and microorganisms), and organic matter on submerged surfaces, rarely venturing into slow-moving or stagnant water.
A minimum tank size of 450 litres is essential for adult L177 plecos, with larger setups (600+ litres) strongly recommended. This species absolutely requires strong water movement and high oxygenation—use powerful external canister filters, additional powerheads, or wavemakers to replicate fast-flowing river conditions. Provide smooth rocks, large pieces of driftwood, caves, and slate shelters to create hiding places and grazing surfaces. Substrate should be smooth sand or fine rounded gravel to protect the delicate ventral surface. Lighting should be moderate to low, with shaded areas under decor. Maintain pristine water quality through robust filtration, frequent large water changes (30-50% weekly), and careful stocking. Avoid sharp decor that may damage fins or barbels.
L177 Gold Nugget Plecos are primarily herbivorous to omnivorous grazers, feeding on biofilm, algae, and organic matter in the wild. In captivity, provide high-quality sinking algae wafers, spirulina pellets, blanched vegetables (zucchini, cucumber, spinach), and occasional protein-rich foods such as frozen bloodworms, mysis shrimp, or live insect larvae. Feed once daily in the evening, as this species is most active after lights-out. Ensure food reaches the bottom and is accessible to this shy, retiring species. Avoid overfeeding and remove uneaten food promptly to maintain water quality. Supplement with wood—Baryancistrus species benefit from grazing on driftwood biofilm and may derive nutritional benefit from lignin.
L177 plecos are peaceful, shy, and primarily nocturnal. During daylight hours, they remain hidden in caves, under driftwood, or behind rockwork. Activity increases at dusk and throughout the night, when they emerge to graze on biofilm and search for food. Males may exhibit territorial behavior toward other Baryancistrus or similar plecos, particularly in smaller tanks or when shelters are limited. They are not aggressive toward other species and generally ignore midwater fish. These plecos are sensitive to poor water quality, low oxygen, and warm stagnant water—stress manifests as lethargy, loss of appetite, and increased susceptibility to disease.
Due to their specific environmental needs, L177 plecos are best kept with peaceful midwater fish that thrive in similar conditions. Suitable tankmates include small to medium characins (tetras, hatchetfish), pencilfish, peaceful dwarf cichlids (Apistogramma), and robust peaceful fish such as larger rasboras or peaceful South American cichlids in very large tanks. Avoid aggressive cichlids, large predatory fish, fin-nipping species, and highly territorial bottom dwellers. Do not house with other Baryancistrus or large Loricariids unless the aquarium is exceptionally spacious with multiple territories. Shrimp and snails are generally ignored. Overcrowded community tanks are unsuitable—this species requires space, excellent water quality, and low stress.
Breeding Baryancistrus sp. L177 in home aquaria is uncommon and challenging. Specific species-level breeding information for L177 is limited, but like other Baryancistrus, spawning likely occurs in caves or narrow crevices, with the male guarding the eggs. Provide large, deep caves or ceramic tubes and maintain pristine water conditions with stable parameters. Seasonal temperature and water chemistry fluctuations may help trigger spawning. Fry are difficult to raise and require specialized care, high water quality, and appropriate first foods. Due to the rarity and expense of this species, breeding attempts should only be undertaken by expert aquarists with suitable setups and resources.
Tropical Fish Co is the UK's leading specialist for rare and premium freshwater fish, including hard-to-find L-number plecos like the L177 Gold Nugget. We source our fish responsibly, quarantine rigorously, and ensure every specimen is healthy, well-conditioned, and ready for your aquarium. Our expert team provides detailed care guidance, and we offer fast, insured nationwide delivery with a live arrival guarantee. Whether you're building a species biotope or seeking a show-stopping centerpiece, Tropical Fish Co delivers quality, expertise, and unmatched customer service. Shop with confidence and discover why thousands of UK aquarists trust us for their most treasured fish.
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